Method of joining closing parts for packaging containers into a web or sheet

Abstract: The invention relates to a method of distributing parts (1) for opening devices and preparing for application in that the parts (1), which are intended to be applied individually on a packaging container, are positioned, closed and marshalled together to form a web or a sheet. The prefabricated parts (1) are arranged in rows x. In each row x, two ore more of the parts (1) are provided with projections (5) which are placed against corresponding part (1) in a neighbouring row and are welded together using ultrasonic means.

Description: TECHNICAL FIELD The present invention relates to a method of distributing and preparing for application, parts for opening devices, each opening device part comprising a pouring part and a closing part, extruded in one piece and in open position, the parts are manufactured in rows and are intended to be applied individiually on a packaging container. BACKGROUND ART Within the packaging industry, relating in particular to packages for liquid foods such as milk and juice, it is a normal occurrence that an opening device is applied on the outside of the packaging container in order to facilitate the consumer's access to the enclosed content. These opening device parts are applied to the outside of the package in an applicator. This applicator most generally operates in such a manner that the objects must be oriented in a given way. In order to facilitate this operation, the objects should, in some way, be held together so that they are oriented in the same way. Furthermore, it should not be possible for the objects to catch in another or lie against one another so that they run the risk of becoming deformed. Such an opening device part which is applied may, for example, consist of an outer pouring and closing device for the package. OBJECTS OF THE INVENTION One object of the present invention is to devise a method of distributing relatively small parts intended to be applied on a packaging container so that the parts are brought, or marshalled, together into a web or a sheet form, which facilitates handling and permits the applicator to be run at higher speed. A further object of the present invention is, by an automatic, continuous process, to unite the individual parts together in a simple and economical manner. SOLUTION These and other objects have been attained according to the present invention by the method of claim 1 wherein the parts connected in rows are positioned and closed in that said pouring part is closed by a snap-in closure to the closing part, that either the pouring part or the closing part on two or more of the parts in a row are provided with a projection and that a number of similarly prepared rows are joined into a web or a sheet in that the projections on one row are welded together with the corresponding opening device parts on a neighbouring row. Preferred embodiments of the present invention have further been given the characterizing features as set forth in the appended subclaims. BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS One preferred embodiment of the present invention will now be described in greater detail hereinbelow, with particular reference to the accompanying Drawings, in which Fig.1 shows a row of opening device parts; Figs. 2 A-G show how the parts are marshalled together in a suitable distribution unit; and Fig. 3 shows how the parts are welded together to web or sheet form. DESCRIPTION OF PREFERRED EMBODIMENT Those opening device parts which are intended to be distributed according to the present invention consist of a pouring part 2 and a closing part 3 manufactured in one piece, which is to be applied on the outside of a packaging container. Such a packaging container may be constituted by a parallelepipedic package consisting of a laminate with an outside of a thermoplastic layer. This parallelepipedic package is provided with an aperture which is covered by a so-called pull-tab, and the opening device part 1 is intended to be applied around and over the pull-tab. Fig. 1 shows a number of parts 1, as they appear when they have been extruded. The parts 1 are manufactured from plastic material. In this phase, the opening device part 1 is open. The pouring part 2 is intended to be fixed against the outside of the packaging container, and the closing part 3 is passed over the pouring part 2. The pouring part 2 and closing part 3 of an opening device part 1 are united by the intermediary of a hinge piece 4. When the parts 1 are extruded, they are united in a row comprising an X number of opening device parts 1. On two or more of the closing parts 3 of the opening device part 1, there are small projections 5 projecting outside the edge, these projections being intended to be used for the uniting of a number of rows into a web form. In Fig. 1, and in the preferred embodiment, the two outermost opening device parts 1 on each side are provided with projections 5, this in order to impart greater stability to the web. Alternatively the projections 5 are provided to the pouring part 2 of the opening device part 1. The parts 1 may be applied on the packaging container in the appearance as shown in Fig. 1, but they may also be closed, in that the closing part 3 is brought together with the pouring part 2 by the whole opening device part 1 being folded over in its hinge piece 4, and closed by means of a snap-in closure. Figs. A-G show the process for obtaining a suitable distribution unit for the above described parts 1. When the parts 1 depart from the extruder 6, they arrive in a number of rows X. Since the extruder 6 is symmetrically designed and constructed, the rows are mirror-reversed in relation to one another, two-by-two. In order to marshal together the objects 1 to web form, every other row must, therefore, be positioned (Fig. 2 B) in that, for example, every other row is lifted by suction cups and rotated through 180°. In the preferred embodiment, the parts 1 are intended to be applied in the closed state, for which reason the closing part 3 must be brought together with the pouring part 2, as shown in Fig. 2 C. Further, the now closed part 1 are marshalled together in a line in sequence after one another as shown in Fig. 2 D. The rows of parts 1 x are retained in a fixture device and are fused or welded together with the subsequent row at the projections 5 with which two or more of the opening device parts 1 are provided. Given that this process is continuous and automatic, the opening device parts 1 will thus be marshalled together to a web or a sheet form. This may possibly be fed directly to an applicator machine, but since manufacture of the parts 1 most generally does not coincide with application of the objects 1 themselves, it is appropriate to sever the web form into suitable pieces y, a sheet, which can be packed in a box or crate to a suitable height z. This is illustrated in Figs. 2 F-G. Fig. 3 shows the welding operation, which is suitably carried out by means of an ultrasonic horn 7 since, by such means, a directed welding will be obtained of the small surfaces which are contemplated here. Another method of bringing together the projections 5 with the immediately subsequent row can be by heating the projections 5 on one row and the opening device parts 1 on the subsequent row to the melting temperature. The projections 5 are placed so that they rest against the hinge piece 4 on the subsequent row and should suitably be so small that they do not obstruct the function of the opening device part 1, nor do they affect its appearance. At the same time, they constitute such slight material quantity that the cost increase will be negligible. As illustrated in Fig. 3, the projections 5 have a minor indication of fracture 6 where they are secured in their opening device part 1 and, when the web or sheet parts 1 are fed to the applicator, the parts 1 are severed from one another partly on the x-axis and partly on the y-axis into individual parts 1 which are taken charge of by the applicator and secured to the outside of the package using a hot-melt process, or alternatively by heating of the opening device part 1 or the outer thermoplastic layer of the package, respectively. As will have been apparent from the foregoing description, the present invention realises a method of distributing separate parts intended to be applied on a packaging container so that the parts are easy to handle and cannot be deformed in the event of unsuitable storage. The method also makes it possible for the applicator to operate with continuous and even advancement of the parts which are correctly oriented, and, as a result the applicator may be run at higher speed. The present invention should not be considered as restricted to that described above and shown on the drawings, many modifications being conceivable without departing from the scope of the appended Claims.

Claims: A method of distributing and preparing for application parts (1) for opening devices, each opening device part (1) comprising a pouring part (2) and a closing part (3) extruded in one piece and in open position, the parts (1) being manufactured in rows and intended to be applied individually on a packaging container, the method being such that the parts (1) connected in rows are positioned and closed in that said pouring part (2) is closed by a snap-in closure to the closing part (3), that either the pouring part (2) or the closing part (3) on two or more of the parts (1) in a row are provided with a projection (5) and that a number of similarly prepared rows are joined into a web or a sheet in that the projections (5) on one row are welded together with the corresponding opening device parts (1) on a neighbouring row. The method as claimed in Claim 1, characterized in that the four outermost parts (1), two on each side, in each row are welded together with corresponding part (1) on a neighbouring row. The method as claimed in Claim 1, characterized in that the parts (1) are welded together by ultrasonic means. The method as claimed in Claim 1, characterized in that the projection (5) is prepared for separation in that the projection (5) has an indication of fracture (6).

Inventors: HAKANSSON JAN, LUNDH KARL-ERIK, HAKANSSON, JAN, LUNDH, KARL-ERIK
Applicants: TETRA LAVAL HOLDINGS & FINANCE, TETRA LAVAL HOLDINGS & FINANCE SA
Application year: 1994
Main classification: B29C65
IPC codes: B65B7, B29L22, B65B17, B29C65, B67B3, B67B7